6ctz

Publication Abstract from PubMed

Aminoglycoside phosphotransferases (APHs) are one of three families of aminoglycoside-modifying enzymes that confer high-level resistance to the aminoglycoside antibiotics via enzymatic modification. This has now rendered many clinically important drugs almost obsolete. The APHs specifically phosphorylate hydroxyl groups on the aminoglycosides using a nucleotide triphosphate as the phosphate donor. The APH(2) family comprises four distinct members, isolated primarily from Enterococcus sp., which vary in their substrate specificities and also in their preference for the phosphate donor (ATP or GTP). The structure of the ternary complex of APH(2)-IIIa with GDP and kanamycin was solved at 1.34 A resolution and was compared with substrate-bound structures of APH(2)-Ia, APH(2)-IIa and APH(2)-IVa. In contrast to the case for APH(2)-Ia, where it was proposed that the enzyme-mediated hydrolysis of GTP is regulated by conformational changes in its N-terminal domain upon GTP binding, APH(2)-IIa, APH(2)-IIIa and APH(2)-IVa show no such regulatory mechanism, primarily owing to structural differences in the N-terminal domains of these enzymes.

Structural basis for the diversity of the mechanism of nucleotide hydrolysis by the aminoglycoside-2-phosphotransferases.,Smith CA, Toth M, Stewart NK, Maltz L, Vakulenko SB Acta Crystallogr D Struct Biol. 2019 Dec 1;75(Pt 12):1129-1137. doi: , 10.1107/S2059798319015079. Epub 2019 Nov 29. PMID:31793906^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.